The United States and Japan will step up their defence cooperation to deal with the threat from nuclear-armed North Korea as tensions in East Asia remain high, officials from the two allies said on Thursday.

SA hotel cleaner was victim of inside job

A terrified hotel cleaner who was threatened with a meat cleaver and a claw hammer during a robbery, later discovered it was an inside job, a judge has been told.

Charles Borgewell, who spent 14 years in the Royal Australian Air Force, said finding out the robbery had been orchestrated by the hotel duty manager left him "distrusting and overcautious" about many people.

His victim impact statement was read out on Tuesday in the South Australian District Court at the sentence hearing of Suzette Patricia Riede, 52, who was found guilty of aggravated robbery.

Riede was managing the Gepps Cross Hotel in July 2011 when her male friend, wearing a balaclava and wielding the meat cleaver and claw hammer, approached Mr Borgewell and tied him up.

Her trial was told CCTV footage of the robber pushing and shoving Riede into a room where the safe was kept was a scam for the cameras.

The robber tied Riede and the cleaner up before fleeing with about $16,000.

Mr Borgewell said he was mentally and physically affected by the robbery, had to move back to Townsville and was unable to work for two years.